Preparation for applying to the hair and skin preparatory to dry-shaving



Patented Dec. 31, 1940 UNITED STATES PATENT OFFICE PREPARATION FOR APPLYING TO THE HAIR AND SKIN PREPAKATOBY T DRY-SHAV- ING Arthur D. Robson, New York, N. Y.

No Drawing. Application December 14, 1939, Serial No. 309,247

6 Claims.

unsupported hair; and, two, it acts as a lubricant facilitating the passage of the blade over the g skin and minimizing the danger bfcutting under shaving pressure. In the absence of a lubricant the frictional resistance of the skin under the pressure exerted by-the blade, which pressure is necessary to cut the hair, causes the skin to rise slightly in advance of the blade and in-' creases the danger of its being cut, particularly when the blade is held at the proper angle for efiicient shaving.

Dry-shaving, as the name implies, dispenseswith lather. The hair projects within a slot or aperture of a shear plate held against the skin and is sheared oil by a cutter moving in shearing relation to one edge of the slot. Softening is not necessary because the action is a shearing, not

a cutting or sawing action, and the hair isamply supported. Lubrication is not necessary because the smooth shear plate moves readily over the skin and there is no sharp cutting edge pressed at an angle against the skin. Not only is the use of lather unnecessary in dry-shaving,

its usewould be disadvantageous. This is not only because oi! clog ing of the fine slots or aperture of the shear plate and cutter, but because the shearing action of the cutter is more efiicient when acting on unsoftened hair projecting from an unsoftened skin. a

It is the object of the present invention to increase the stifiness of the hair and skin and thus Prep re them for still more efiicient dry-shaving.

I have attained this object by applying to the hair and skin, prior to dry-shaving, a liquid dispersion of a water soluble alkyl cellulose ether in an appropriate vehicle, such as a mixture of ethyl alcohol and water, forming a liquid or jelly which, on evaporation of the vehicle after application, stifiens and hardens the hair and skin, and which forms an imperfect or discontinuous film that does not interfere with the operation of the dry-shaver and is readily soluble in water and thus easily washed off after shaving. Both human hair and epidermis, the outer stratum of the skin, are composed chiefly of keratin, a highly complex organic substance comprising nitrogen and sulphur. Keratin is insoluble in water but absorbs it readily, and the hardness oi! both hair and skin are decreased by water-absorption. I have discovered, however, that when hair and skin are treated with an aqueous alcohol dispersion or an alkyl cellulose ether, as for example a 7% to 8% dispersion of 5 methyl cellulose in aqueous ethyl alcohol containing about 30% water, the hair and skin, instead of being softened, as with water, are left measurably stiffened after the aqueous alcohol hasevaporated, which it quickly does. A 7%-8% 10 dispersion of methyl cellulose in aqueous ethyl alcohol is particularly advantageous, but the proportions of the alkyl cellulose ether are not critical. A minimum sufilcient to form a film and a maximum short of that forming a jelly too 1 thick for application comprehend the useful range. The proportions of water and alcohol in the vehicle mixture best approximate 30% water and 70% alcohol, but again the proportions are not critical. It the aqueous'alcohol contains less 20 than about 20% of water the dispersion will not usually contain enough of the alkyl cellulose ether to form a satisfactory film, and if it contains more than about 40% or 50% the dispersion tends to dry too slowly. Perfume is with advan- 25 tage included in the dispersion. Coloring agents and similar compounding materials may be included. The hair in this stiflened condition is sheared more easily and efiiciently than normal hair. The film remaining on the skin after 30 evaporation of the aqueous alcohol is discontinuous and does not interfere with the passage of the shear plate over the skin. The material of the film does not clog or otherwise interfere with the operation of the dry shaver, but instead 35 aids in maintaining free operation 01 the dry shaver, this material plus sheared hair forming a powdery and fiufi'y eiiluent easily and continuously discharged by the dry shaver. And finally,

all traces of the film may be readily removed at 40 the end of the shaving operation by simply washing the skin with water.

This application is a continuation-in-part of my earlier application Serial No. 300,389, filed October 20, 1939.

I claim:

1. A preparation for applying to the hair and skin preparatory to dry-shaving which comprises a liquid dispersion of a water soluble alkyl cellulose ether in aqueous alcohol, said preparation, after application to the hair and skin and evaporation of the aqueous alcohol, leaving a discontinuous film which stiiiens the hair.

2. A preparation for applying to the hair and skin preparatory to dry-shaving which comprises a liquid dispersion of a water soluble alkyl cellulose ether in aqueous alcohol containing about 30% water, said preparation, after application to the hair and skin and evaporation of the aqueous alcohol, leaving a discontinuous film which stiflens the hair.

3. A preparation for applying to the hair and skin preparatory to dry-shaving which comprises a liquid dispersion of about 7%-8% of a water soluble alky'l cellulose ether in aqueous alcohol containingabout 30% water, said preparation, after application. to the hair and skin and evaporation of the aqueous alcohol, leaving a discontinuous film which stifiens the hair. 1

4. A preparation for applying to the hair and skin preparatory to dry-shaving which comprises and skin and evaporation of the aqueous alcohol,

leaving a discontinuous film which stiflens the a liquid dispersion of about 7%-8% oi' a' 'water soluble alkyl cellulose ether in aqueous alcohol containing about 30% water and a perfume, 15

said preparation, afterv application to the hair and skin and evaporation of the aqueous alcohol,

leaving a discontinuous film which stiifens the I hair.

ARTHUR D. ROBSON. 

